Part 4: Break Things Up

An important parameter group in PhysX Glue is Breakability, which deletes the bindings when the particles encounter sufficient force.

  1. Click the PhysX Glue test and on the Parameters rollout, turn on Breakable By Force in the Breakability group. Click the > button on the time slider a couple of times while watching a viewport in which the bindings are visible.

    By frame 2, all the bindings are gone. Because the default Max Force and Max Torque settings are low, the gravity force alone is enough to dissolve the bonds.

    Max Force and Max Torque define the maximum forces that a binding can withstand before breaking. To create a realistic simulation, you usually need to increase both values.

  2. At a frame before the ball hits the wall – say, 6 – increase Max Force and Max Torque until the bindings are visible again. For example, try setting both to 500.

  3. Continue experimenting with the Max Force and Max Torque settings while playing the animation to see the different effects possible. Also try adjusting the Birth Stream > Speed value to see how it affects the simulation.

    When you're done, restore both Max Force and Max Torque to 1.0, and Birth Stream > Speed to 300.